Introduction: The use of anti-tumour necrosis factor (anti-TNF) therapy is increasing in the treatment of rheumatoid arthritis (RA), spondyloarthropathy, psoriasis and inflammatory bowel disease. It is being debated whether treatment of patients with rheumatic diseases with anti-TNF therapy is associated with an increased cancer incidence.
Material and methods: A descriptive study of cancer cases among 3,688 patients with rheumatic diseases who received anti-TNF therapy was performed. The patients were identified in the nationwide database DANBIO and had a total number of treatment years of 6,092 years. All cancer cases were identified and the cancer diagnoses were subsequently confirmed by medical record review.
Results: A total of 30 cancers in 28 of 3,688 patients were registered in the DANBIO after initiation of anti-TNF therapy in the period from October 2000 to June 2007. Among these six men and 20 women had RA, and two men had Morbus Becterew. The following cancer types were observed: malignant lymphoma 2 (7%), lung 4 (13%), plicae vocalis 2 (7%), breast 4 (13%), pancreatic 3 (10%), colorectal 2 (7%), prostate 1 (3%), malignant melanoma 3 (10%) and non-melanoma skin cancer 9 (30%).
Conclusion: In our descriptive study from the nationwide database DANBIO, a total of 30 cancers were observed in 3,688 patients with rheumatic diseases within a cumulated period of treatment with anti-TNF of 6,092 years. Follow-up for anti-rheumatic and adverse effects in patients in the DANBIO database will continue. Future studies must reveal whether anti-TNF therapy is associated with an increased cancer risk. Planned Danish studies will include relevant control groups and adjustment for confounders.